Comment spam

Comment spam is a term referencing a broad category of spambot or spammer postings which abuse web-based forms to post unsolicited advertisements as comments on forums, blogs, wikis and online guestbooks. Related topics include:
 * Forum spam, posts on Internet forums that contains related or unrelated advertisements, links to malicious websites, and abusive or otherwise unwanted information
 * Newsgroup spam, a type of spam where the targets are Usenet newsgroups
 * Social spam, unwanted spam content appearing on social networks and any website with user-generated content
 * Spam in blogs, a form of spamdexing done by posting random comments, copied material, or promotion of commercial services
 * Troll (Internet), a person who sows discord on the Internet
 * Hit-and-run posting, a tactic where a poster at an Internet forum enters, makes a post, only to disappear immediately after
 * Sockpuppet (Internet), an online identity used for purposes of deception
 * Astroturfing, the practice of masking the sponsors of a message or organization